A photobioreactor (PBR) is a bioreactor that includes one or more phototrophic organisms suspended in volume of liquid enclosed in a compartment that is at least partially transparent and that is exposed to light. PBRs can be used to cultivate or farm phototrophic organisms in high concentrations while preventing contamination from other undesired organisms, and can allow for a high degree of control over conditions such as pH, light intensity, carbon dioxide concentration, and temperature.
The materials forming the walls of the compartments in a PBR must allow for high light transmittance while also maintaining adequate strength over long time periods in wet environments.